Method of producing shaped cellulosic articles

Abstract

Shaped cellulosic bodies and especially cellulosic fibers or filaments are produced by precipitating cellulose from a solution containing cellulose and NMMO. To allow elevated concentrations of NMMO in the precipitating bath without detriment to the properties of the fibers or filaments produced, the temperature of the precipitating bath is held at most at 0 DEG C.

We claim: 
     
       1. A process for producing a shaped cellulosic article which comprises the steps of: (a) forming a solution of cellulose in N-methylmorpholine-N-oxide and water;   (b) shaping said solution;   (c) passing the shaped solution through an air gap into a precipitating bath containing water and N-methylmorpholine-N-oxide to coagulate the cellulose and form said article; and   (d) maintaining the temperature of said bath during the coagulation of cellulose to form said article therein at 0° C. at the most.   
     
     
       2. The method defined in claim 1 wherein the concentration of N-methylmorpholine-N-oxide in said precipitating bath is maintained above 28%. 
     
     
       3. The method defined in claim 1 wherein the concentration of N-methylmorpholine-N-oxide in said precipitating bath is maintained at about 30 to 40%. 
     
     
       4. The method defined in claim 3, further comprising the step of passing said shaped solution through an air gap before contacting it with said precipitating bath. 
     
     
       5. The method defined in claim 4, further comprising stretching said solution in said air gap. 
     
     
       6. The method defined in claim 5 wherein said solution is shaped by pressing it through an orifice in a spinneret to form a fiber.